Recent requirements of the electronics industry for purer gases and verification of contaminant levels have increased interest in the use of zeolitic adsorbents for removing trace nitrogen from argon. Divalent chabazites have been disclosed as useful adsorbents for removing trace nitrogen from argon, for purifying methane, and for quantitatively separating oxygen from argon in chromatographic applications. The intrinsic properties of chabazites expand the range of contaminant gases which can be removed economically from bulk gases using standard adsorption techniques and the calcium form of chabazite, properly activated, is perhaps the most energetically sorbing molecular sieve for both polar and non-polar gases.
However, the availability of high-grade chabazite is extremely limited. Pure chabazite exists only rarely in nature and is too expensive to be used as a commercial adsorbent. Synthetic analogues of chabazite are known and have been designated D, R, G, and ZK-14 (Breck, Zeolite Molecular Seives, John Wiley and Sons, New York, N.Y., p 110 (1974) and Cartleidge et al., Zeolites. 4, 226 (1984}). However, known methods for preparing commercially useful synthetic chabazites are not practical since they suffer from low yields, poor product purity, long cystallization times, and are difficult if not impractical to scale-up. Chabazite-based adsorbents will only be fully exploitable commercially when an economic chabazite having sufficiently improved adsorbing properties for weakly interacting adsorbates is available on a large scale.